Police are searching for the gunman who critically injured a man in the U-District neighborhood of Seattle early Saturday.

Officers patrolling the area of 12th Avenue Northeast and Northeast 42nd Street just before 2 a.m. said they heard shots fired, and responded to the scene when a 911 call came in saying that a man had been shot.

Seattle Police Det. Renee Witt said the officers found a man "with a gunshot wound to the chest that exited out of his groin area." The man was rushed to Harborview Medical Center in critical condition.

Multiple pedestrians were in the area but told officers they didn't see what happened. One witness who was called back to the scene said he saw the shots being fired but ran from the area and was unable to provide any more details.

Evidence technicians found shell casings and clothing at the scene, officials said.

No other injuries or damage were reported. It remains unclear what caused the incident, and detectives are working to determine who shot the victim.